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6th International ICST Conference on wireless Internet, WICON 2011

作者： Jiang, Haifang Zhang, Sihai Zhou, Wuyang Wireless Information Network Lab. Department of Electronic Engineering and Information Science University of Science and Technology of China Hefei Anhui 230026 China Key Laboratory of Wireless Sensor Network and Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences 865 Changning Road Shanghai 200050 China

ISBN: (纸本)9783642304927

In this paper, distributed relay selection algorithms based on statistical Channel State Information (CSI) in amplify-and-forward mode are proposed, aiming to maximize energy efficiency. With the limited CSI, a tradeoff is made between the total power consumption and the target outage probability at the source. A forwarding threshold is obtained by minimizing the average transmission power. Each relay individually decides whether to participate in forwarding the source signals according to the forwarding threshold. Firstly, a Distributed Multiple Relay Selection (DMRS) algorithm is proposed, in which all candidate relays have the possibility of transmitting the source signals and the threshold is obtained by numerical search. Then a Distributed Single Relay Selection (DSRS) algorithm with low complexity is investigated under the assumption that only one relay forwards the signals. Simulation results indicate that the proposed algorithms provide significant performance gain in terms of energy efficiency over the existing AF-mode relay selection algorithms. © 2012 ICST Institute for Computer Science, Social Informatics and Telecommunications Engineering.

关键词： Energy efficiency

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The master-slave stochastic knapsack modelling for fully dynamic spectrum allocation

The master-slave stochastic knapsack modelling for fully dyn...

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6th International ICST Conference on wireless Internet, WICON 2011

作者： Zhang, Sihai Yang, Fei Zhou, Wuyang Wireless Information Network Lab. Department of Electronic Engineering and Information Science University of Science and Technology of China Hefei Anhui 230026 China Key Laboratory of Wireless Sensor Network and Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences 865 Changning Road Shanghai 200050 China

ISBN: (纸本)9783642304927

Scarcity problem of radio spectrum resource stimulates the research on cognitive radio technology, in which dynamic spectrum allocation attracts lots of attention. For higher access efficiency in cognitive radio context, we suggest a fully dynamic resource allocation scheme for primary and secondary users, which is modelled by a master-slave stochastic knapsack process. Equilibrium behavior is analyzed, and expressions of blocking probability of both slave and master classes are derived as performance criterion and verified by numeric simulation, as well as forced termination probability of the secondary users. Compared to traditional opportunistic spectrum access (OSA), which can be regarded as half dynamic, our scheme leads to less termination events for the slaves while keeping the same behavior for the master class, promoting the system access performance. © 2012 ICST Institute for Computer Science, Social Informatics and Telecommunications Engineering.

关键词： Cognitive radio

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A full-rate cooperative communication strategy in wireless relay networks

A full-rate cooperative communication strategy in wireless r...

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6th International ICST Conference on wireless Internet, WICON 2011

作者： Zhan, Lei Yang, Fei Zhang, Sihai Zhou, Wuyang Wireless Information Network Lab. Department of Electronic Engineering and Information Science University of Science and Technology of China Hefei Anhui 230026 China Key Laboratory of Wireless Sensor Network and Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences 865 Changning Road Shanghai 200050 China

ISBN: (纸本)9783642304927

In this paper, we propose a new full-rate cooperative communication strategy in wireless relay networks without direct path between source and destination. This strategy coined full-rate amplify-and-forward (FRAF) utilizes multiple relay nodes to take turns to amplify and forward data package for the transmitter at different time slot. Thus the source node could continue sending without cessation. On the other hand, prevailing linear constellation precoding process is adopted at the source node to solve the problem caused by the imbalance of the error performance of the data sent at odd and even time slots. Furthermore, we analyze the outage probability and certificate that FRAF strategy can achieve the full diversity gain. The simulation results indicate that FRAF could improve the performance of the system effectively compared to the conventional amplify-and-forward (AF) and decode-and-forward (DF) strategy. © 2012 ICST Institute for Computer Science, Social Informatics and Telecommunications Engineering.

关键词： Cooperative communication

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Optimal power allocation and relay selection for cognitive two-way AF relaying network

Optimal power allocation and relay selection for cognitive t...

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IET International Conference on Information Science and Control Engineering 2012 (ICISCE 2012)

作者： Ronghua Luo Zhen Yang Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications China

ISBN: (纸本)9781629939254

In an underlay cognitive two-way Amplify-and-Forward (AF) relaying network, secondary users (SUS) and primary user (PU) can share the licensed spectrum simultaneously under the interference threshold constraint. In this paper, the joint power allocation and optimal relay selection scheme is proposed for allocating radio resource on cognitive nodes effectively. For power allocation problem, the objective function is to maximize the achieved minimum Signal to Interference plus Noise Ratio (SINR) at SUS, and the constraints include the total transmit power of cognitive nodes and PU interference threshold, the optimal power allocation algorithm and a simple distributed power allocation algorithm are proposed. Furthermore, based on these results, an optimal two-way relay selection scheme is proposed. Simulation results show that the proposed joint power allocation algorithms and relay selection scheme can achieve excellent system performance.

关键词： Cognitive two-way AF relaying Interference threshold Power allocation Relay selection power splitting interference threshold Allocation Algorithm Transmitter power relay Bidirectional

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A novel channel estimation method for clipped OFDM systems based on virtual pilots

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Journal of Computational Information Systems 2012年第5期8卷 1905-1912页

作者： Xie, Yongsheng Zhou, Leilei Fu, Yaoxian Key Lab. of Wireless Sensor Network and Communication Shanghai Institute of Microsystem and Information Technology CAS Shanghai 200050 China

Data as well as pilot symbols are nonlinearly distorted due to signal clipping in practical OFDM systems. The distortion inflicted on pilot symbols has great negative effect on the channel estimation. To solve this issue, a novel iterative channel estimation algorithm based on virtual pilots is introduced for clipped OFDM systems in this paper. The algorithm iteratively estimates nonlinear distortion of data symbols, and subsequently uses it for data detection. Then part or all of the detected data symbols are used as virtual pilots to perform more precise channel re-estimation. The MSE of channel estimation is derived theoretically. Simulation results show that the proposal improves the performance remarkably with moderate complexity increase at the receiver. In particular, compared to traditional algorithm, the BER performance of this method increases by 0.3 dB. © 2012 Binary Information Press.

关键词： Peak to average power ratio

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A load-balanced data aggregation scheduling for duty-cycled wireless sensor networks

A load-balanced data aggregation scheduling for duty-cycled ...

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2012 4th IEEE International Conference on Cloud Computing technology and Science, CloudCom 2012

作者： Chen, Zhengyu Yang, Geng Chen, Lei Xu, Jian Wang, Haiyong Key Lab of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts AndTelecommunications Nanjing 210046 China College of Computer Science and Technology Nanjing University of Posts and Telecommunications Nanjing 210046 China School of Information Technology Jinling Institute of Technology Nanjing 211169 China

ISBN: (纸本)9781467345095

To bridge the gap between limited energy supplies of the sensor nodes and the system lifetime, duty-cycle wireless sensor networks (WSNs) with data aggregation are studied in this paper. We proposed a load-balanced and latency-efficient data aggregation scheduling for duty-cycled WSNs. A shortest path tree (SPT) is used as the routing structure for data aggregation scheduling. In SPT, parent-children assignments are well-designed to assign nodes from level h+1 to the parents at level h such that every parent has a balanced load, while reducing the sleep latency which is a period of time for a sender to wait for its parent to be active. Finally, through the simulation and comparisons, we prove the effectiveness of our approach. © 2012 IEEE.

关键词： Scheduling

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A trustworthy network architecture based on strengthen TNC

International Journal of Digital Content Technology and its ...

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International Journal of Digital Content technology and its Applications 2012年第17期6卷 343-349页

作者： Yin, Ansheng Zhang, Shunyi Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education China Institute of Information and Network Technology Nanjing University of Posts and Telecommunication China

As networks have grown in size and complexity, the existing isolated add-on security systems of internet are confronting some serious challenges. This paper outlines the background, concept, evolution and basic properties of the trustworthy network, and projects the future development of the network in terms of its access control, modeling of trust relationship, quantification and decisionmaking. Then put forward a strengthen TNC to fix the deficiencies.

关键词： network architecture

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Dynamical QoS self-configuration approach of cognitive networks based on end-link cooperation policy

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Journal of Computational Information Systems 2012年第11期8卷 4685-4693页

作者： Qi, Jin Zhang, Shunyi Sun, Yanfei Key Lab. of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China Institute of Information and Network Technology Nanjing University of Posts and Telecommunication Nanjing 210003 China

To solve the problem of rapid QoS declining under network situation as well as improve the judging and dynamical adjusting ability that network system towards user QoS, in this paper, we proposed a dynamical self-configuration approach for guaranteeing QoS in cognitive networks (CNs). Through utilizing the active property of CNs while introducing end-link cooperation policy based on decisionmaking, the user priority has been determined and dynamically corrected. The simulation result represents that the proposed approach has better performance than traditional best of effort service, enabling to guarantee the user QoS under congestion status effectively. © 2012 Binary Information Press.

关键词： Quality of service

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A sliding fractal autoregressive integrated moving average model based on time compensation: SFARIMA

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Advances in Information Sciences and Service Sciences 2012年第19期4卷 11-17页

作者： Yin, An-sheng Zhang, Shun-yi Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education China Institute of Information and Network Technology Nanjing University of Posts and Telecommunication China

The traditional Poisson model in the modern data networks have been ineffective and cannot reflect the real flow trend. However, since Hosking discovers the network traffic self-similarity, self-similar models have continued to emerge, this article improved FARIMA model based on time compensation. We put forward a sliding FARIMA model which fixes the time delay of FARIMA model and analyzed the model's application in the anomaly detection of network.

关键词： Software engineering

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Cognitive networks multi-constraint QoS routing algorithm based on autonomic ant colony algorithm

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Journal of Computational Information Systems 2012年第8期8卷 3429-3436页

作者： Qi, Jin Zhang, Shunyi Sun, Yanfei Key Lab. of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China Institute of Information and Network Technology Nanjing University of Posts and Telecommunication Nanjing 210003 China

This paper focused on the study of cognitive networks (CNs) oriented multi-parameter constraint Quality of Service (QoS) routing optimization. With the foundation of CNs multi-parameter QoS routing requirement, referring to the shortcomings of basic ant colony algorithm, we brought improvements to the four aspects of pheromone initialization, pheromone evaporation factor adjustment, pheromone update method and state transition rules, proposed the CNs multi-constraint QoS routing algorithm based on autonomic ant colony (AAC) algorithm. The simulation result represents that the proposed algorithm has relatively good optimization ability and fast convergence speed, can effectively solving the multi-constraint QoS routing problem faced by CNs. © 2012 Binary Information Press.

关键词： Cost functions

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